Linus,

please pull the latest sched-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
sched-urgent-for-linus

A pile of rseq related fixups:

 - Prevent infinite recursion when delivering SIGSEGV

 - Remove the abort of rseq critical section on fork() as syscalls inside
   rseq critical sections are explicitely forbidden. So no point in doing
   the abort on the child.

 - Align the rseq structure on 32 bytes in the ARM selftest code.

 - Fix file permissions of the test script

Thanks,

        tglx

------------------>
Mathieu Desnoyers (3):
      rseq/selftests: Make run_param_test.sh executable
      rseq/selftests/arm: Align 'struct rseq_cs' on 32 bytes
      rseq/cleanup: Do not abort rseq c.s. in child on fork()

Will Deacon (1):
      rseq: Avoid infinite recursion when delivering SIGSEGV


 arch/arm/kernel/signal.c                       |  4 ++--
 arch/powerpc/kernel/signal.c                   |  4 ++--
 arch/x86/entry/common.c                        |  2 +-
 arch/x86/kernel/signal.c                       |  2 +-
 include/linux/sched.h                          | 23 ++++++++++++-----------
 kernel/rseq.c                                  |  7 ++++---
 tools/testing/selftests/rseq/rseq-arm.h        |  1 +
 tools/testing/selftests/rseq/run_param_test.sh |  0
 8 files changed, 23 insertions(+), 20 deletions(-)
 mode change 100644 => 100755 tools/testing/selftests/rseq/run_param_test.sh

diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index f09e9d66d605..dec130e7078c 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -544,7 +544,7 @@ static void handle_signal(struct ksignal *ksig, struct 
pt_regs *regs)
         * Increment event counter and perform fixup for the pre-signal
         * frame.
         */
-       rseq_signal_deliver(regs);
+       rseq_signal_deliver(ksig, regs);
 
        /*
         * Set up the stack frame
@@ -666,7 +666,7 @@ do_work_pending(struct pt_regs *regs, unsigned int 
thread_flags, int syscall)
                        } else {
                                clear_thread_flag(TIF_NOTIFY_RESUME);
                                tracehook_notify_resume(regs);
-                               rseq_handle_notify_resume(regs);
+                               rseq_handle_notify_resume(NULL, regs);
                        }
                }
                local_irq_disable();
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index 17fe4339ba59..b3e8db376ecd 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -134,7 +134,7 @@ static void do_signal(struct task_struct *tsk)
        /* Re-enable the breakpoints for the signal stack */
        thread_change_pc(tsk, tsk->thread.regs);
 
-       rseq_signal_deliver(tsk->thread.regs);
+       rseq_signal_deliver(&ksig, tsk->thread.regs);
 
        if (is32) {
                if (ksig.ka.sa.sa_flags & SA_SIGINFO)
@@ -170,7 +170,7 @@ void do_notify_resume(struct pt_regs *regs, unsigned long 
thread_info_flags)
        if (thread_info_flags & _TIF_NOTIFY_RESUME) {
                clear_thread_flag(TIF_NOTIFY_RESUME);
                tracehook_notify_resume(regs);
-               rseq_handle_notify_resume(regs);
+               rseq_handle_notify_resume(NULL, regs);
        }
 
        user_enter();
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index 92190879b228..3b2490b81918 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -164,7 +164,7 @@ static void exit_to_usermode_loop(struct pt_regs *regs, u32 
cached_flags)
                if (cached_flags & _TIF_NOTIFY_RESUME) {
                        clear_thread_flag(TIF_NOTIFY_RESUME);
                        tracehook_notify_resume(regs);
-                       rseq_handle_notify_resume(regs);
+                       rseq_handle_notify_resume(NULL, regs);
                }
 
                if (cached_flags & _TIF_USER_RETURN_NOTIFY)
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 445ca11ff863..92a3b312a53c 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -692,7 +692,7 @@ setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
         * Increment event counter and perform fixup for the pre-signal
         * frame.
         */
-       rseq_signal_deliver(regs);
+       rseq_signal_deliver(ksig, regs);
 
        /* Set up the stack frame */
        if (is_ia32_frame(ksig)) {
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 87bf02d93a27..9256118bd40c 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1799,20 +1799,22 @@ static inline void rseq_set_notify_resume(struct 
task_struct *t)
                set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
 }
 
-void __rseq_handle_notify_resume(struct pt_regs *regs);
+void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs);
 
-static inline void rseq_handle_notify_resume(struct pt_regs *regs)
+static inline void rseq_handle_notify_resume(struct ksignal *ksig,
+                                            struct pt_regs *regs)
 {
        if (current->rseq)
-               __rseq_handle_notify_resume(regs);
+               __rseq_handle_notify_resume(ksig, regs);
 }
 
-static inline void rseq_signal_deliver(struct pt_regs *regs)
+static inline void rseq_signal_deliver(struct ksignal *ksig,
+                                      struct pt_regs *regs)
 {
        preempt_disable();
        __set_bit(RSEQ_EVENT_SIGNAL_BIT, &current->rseq_event_mask);
        preempt_enable();
-       rseq_handle_notify_resume(regs);
+       rseq_handle_notify_resume(ksig, regs);
 }
 
 /* rseq_preempt() requires preemption to be disabled. */
@@ -1831,9 +1833,7 @@ static inline void rseq_migrate(struct task_struct *t)
 
 /*
  * If parent process has a registered restartable sequences area, the
- * child inherits. Only applies when forking a process, not a thread. In
- * case a parent fork() in the middle of a restartable sequence, set the
- * resume notifier to force the child to retry.
+ * child inherits. Only applies when forking a process, not a thread.
  */
 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
 {
@@ -1847,7 +1847,6 @@ static inline void rseq_fork(struct task_struct *t, 
unsigned long clone_flags)
                t->rseq_len = current->rseq_len;
                t->rseq_sig = current->rseq_sig;
                t->rseq_event_mask = current->rseq_event_mask;
-               rseq_preempt(t);
        }
 }
 
@@ -1864,10 +1863,12 @@ static inline void rseq_execve(struct task_struct *t)
 static inline void rseq_set_notify_resume(struct task_struct *t)
 {
 }
-static inline void rseq_handle_notify_resume(struct pt_regs *regs)
+static inline void rseq_handle_notify_resume(struct ksignal *ksig,
+                                            struct pt_regs *regs)
 {
 }
-static inline void rseq_signal_deliver(struct pt_regs *regs)
+static inline void rseq_signal_deliver(struct ksignal *ksig,
+                                      struct pt_regs *regs)
 {
 }
 static inline void rseq_preempt(struct task_struct *t)
diff --git a/kernel/rseq.c b/kernel/rseq.c
index ae306f90c514..22b6acf1ad63 100644
--- a/kernel/rseq.c
+++ b/kernel/rseq.c
@@ -251,10 +251,10 @@ static int rseq_ip_fixup(struct pt_regs *regs)
  * respect to other threads scheduled on the same CPU, and with respect
  * to signal handlers.
  */
-void __rseq_handle_notify_resume(struct pt_regs *regs)
+void __rseq_handle_notify_resume(struct ksignal *ksig, struct pt_regs *regs)
 {
        struct task_struct *t = current;
-       int ret;
+       int ret, sig;
 
        if (unlikely(t->flags & PF_EXITING))
                return;
@@ -268,7 +268,8 @@ void __rseq_handle_notify_resume(struct pt_regs *regs)
        return;
 
 error:
-       force_sig(SIGSEGV, t);
+       sig = ksig ? ksig->sig : 0;
+       force_sigsegv(sig, t);
 }
 
 #ifdef CONFIG_DEBUG_RSEQ
diff --git a/tools/testing/selftests/rseq/rseq-arm.h 
b/tools/testing/selftests/rseq/rseq-arm.h
index 3b055f9aeaab..3cea19877227 100644
--- a/tools/testing/selftests/rseq/rseq-arm.h
+++ b/tools/testing/selftests/rseq/rseq-arm.h
@@ -57,6 +57,7 @@ do {                                                          
        \
 #define __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown,          \
                                abort_label, version, flags,            \
                                start_ip, post_commit_offset, abort_ip) \
+               ".balign 32\n\t"                                        \
                __rseq_str(table_label) ":\n\t"                         \
                ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
                ".word " __rseq_str(start_ip) ", 0x0, " 
__rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \
diff --git a/tools/testing/selftests/rseq/run_param_test.sh 
b/tools/testing/selftests/rseq/run_param_test.sh
old mode 100644
new mode 100755

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